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Evolution

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Humans are still evolving: study. Have we stopped evolving? Whether the human race is still adapting to our surroundings is heavily debated – and now fresh genetic analyses by Harvard University’s Jonathan Beauchamp suggest natural selection still has a part to play. Beauchamp, publishing in the Proceedings of the National Academy of Sciences, compared genomes and traits of 20,000 older people with the number of children they’d produced, and found natural selection favours less schooling and a higher age of first menstruation.

In 1859, Charles Darwin defined natural selection as “one general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die”. The “strong” genes that help a species survive become more common over successive generations. Those traits – and any traits that arise from your genes – are called phenotypes. Is he right? But there are a number of limitations to the work, Beauchamp admits. Nor does it account for fertility timing. Dear Science: Why aren’t apes evolving into humans? (Rachel Orr/The Washington Post) Dear Science: Why are there no hominins left on Earth? If evolution is ongoing and species are always changing and adapting, shouldn't we see new human-like species evolving from apes, even if the old ones died out?

Here's what science has to say: We hate to be the ones to break it to you, but you are an ape. So were the Neanderthals, the Hobbits, Lucy the Australopithecus, the Taung child and Peking man. And there are hominins left on Earth — us. First of all, the creatures we call apes are our cousins, not our ancestors. [Dear Science: Why am I always cold indoors?] "Asking why an archaic human isn't evolving from gorillas today is like asking why the children of your cousins don't look more like you," said Matt Tocheri, an anthropology professor at Lakehead University and a researcher in the National Museum of Natural History's Human Origins Program. [Dear Science: What does sunscreen SPF mean, and what happens if you mix them?]

National health-science true. Businessinsider. Why does life exist? Popular hypotheses credit a primordial soup, a bolt of lightning and a colossal stroke of luck. But if a provocative new theory is correct, luck may have little to do with it. Instead, according to the physicist proposing the idea, the origin and subsequent evolution of life follow from the fundamental laws of nature and “should be as unsurprising as rocks rolling downhill.” From the standpoint of physics, there is one essential difference between living things and inanimate clumps of carbon atoms: The former tend to be much better at capturing energy from their environment and dissipating that energy as heat.

Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. Kristian Peters Cells from the moss Plagiomnium affine with visible chloroplasts, organelles that conduct photosynthesis by capturing sunlight. Courtesy of Jeremy England Wilson Bentley. Ancient shoulders show signs of humanity’s ape-like past. In some ways, chimpanzees seem less primitive than humans. (AP Photo/Martin Meissner) A new study puts the burden of humanity's evolution on our shoulders.

Like, literally on our shoulders. By examining the shoulder blades of two early human Australopithecus species, researchers believe they've found further evidence that humans and apes shared an ape-like ancestor. [Scientists find the oldest-ever hand bone to resemble a modern human’s] Humans are, of course, most closely related to the great apes of Africa -- chimps and bonobos, specifically.

That's already established. That's led some scientists to suggest that our common ancestor was actually more like a monkey, allowing humans to retain some of these primitive features -- like a spine more suited for looking down at tools than for hanging from branches -- while evolving, by chance and by nature of our similar habitats, some of the same advanced adaptations as apes. [Scientists discover a new human ancestor that roamed with ‘Lucy’]

Richard Dawkins vs Peter Boghossian. The Smell of Evolution. Evolution drives relentlessly forward, leaving behind a messy wake. One of the best places to survey its sloppy creativity is inside your nose. When you smell a lily or a cigar or a jug of spoiled milk, you are grabbing their molecules out of an ocean of air. You have exposed nerve endings dangling deep inside your nostrils, each of which is studded with proteins called olfactory receptors. Each neuron is covered in one type of receptor, the shape of which allows it to grab tightly onto certain odor molecules and weakly to others, while letting many others drift by. Snagging a molecule causes the receptor to squirm, leading to a falling-domino-like series of reactions that ends with the neuron firing an electric signal into your brain. The brain gets signals from thousands of neurons in our noses, creating a distinctive signature for each kind of smell we perceive.

But they’ve also found something else that’s rather stunning. Over the next 200 million years, full-blown fish evolved. Barbara Natterson-Horowitz: What veterinarians know that doctors don't. Selman v. Cobb County School District. Background[edit] The statement "evolution is a theory and not a fact" has been used as a tactic by creationists and intelligent design advocates, causing confusion over the difference between how theory is defined and used in the field of science and how the term is used colloquially to signify "conjecture", "speculation" or "opinion".[3] Both the teaching of creationism and intelligent design in state schools in the USA have been challenged in court and found to be a violation of the Establishment Clause (notably Edwards v.

Aguillard, Kitzmiller v. Dover Area School District). Those cases followed an earlier constitutional court ruling against religiously based bans against the teaching of evolution (Epperson v. Arkansas). In 1997 a school policy adopted in Louisiana requiring the reading of a prepared statement before any teaching of evolution was also judged as unconstitutional (Freiler v. In 2001 the Cobb County School District began the process of adopting new science textbooks. Pat Robertson Attacks Ken Ham and Creationism after Bill Nye Science Guy Debate. What Is the Evidence for Evolution Found in the Fossil Record? Richard Dawkins Speech (2009)

Ed Yong: Suicidal crickets, zombie roaches and other parasite tales | Talk Video. Why penguins stopped flying | The Sideshow. Birds like murres helped researchers understand why penguins no longer fly (Live Science) Penguins are excellent swimmers. But even with wings, the aquatic flightless birds do not take to the skies despite having wing-like flippers. In fact, a new study says that penguins became so good at swimming that they eventually evolved to specialize at that skill at the cost of airborne flight. "Like many people, I've always been interested in penguins, and seeing them do these phenomenal marches across the ice, I've often thought: 'Why don't they just fly? ' Professor John Speakman, from the University of Aberdeen and the Chinese Academy of Sciences, told the BBC. " The new study, published in the Proceedings of the National Academy of Sciences, says that at least five species of penguin have adapted into flightless birds.

In fact, many studies compare penguins’ underwater prowess to being like flight beneath the waves. "The energy costs are very, very high,” Speakman said. Why Evolution is True and Why Many People Still Don't Believe It (Jerry Coyne, 2012) Daniel Dennett Doing What He Does. David Sloan Wilson on Richard Dawkins. John McWhorter: Txtng is killing language. JK!!! Colin Camerer: Neuroscience, game theory, monkeys. Missing Link For Wonky-Eyed Fish Discovered. The face of a flounder, sole, halibut or other flatfish looks like a hodgepodge of mismatched puzzle pieces forced together, with eyes that don't seem to match one another nor the orientation of the animal's mouth.

This is because, as these fish mature, one eye migrates over the top of the fish's head, coming to rest above the other eye, so both are on the same side of the head. A new fossil discovery has shed light on how this strange trait came about. Matt Friedman, a paleobiologist at University of Oxford in the United Kingdom, found a sort of flatfish missing link in a drawer of unidentified fish fossils in the Natural History Museum of Vienna, Austria. [Image Gallery: Freaky Fish] The left eye of this single specimen, a 50-million-year-old fish called Heteronectes, has migrated toward the top of the skull, but not all the way over.

There are about 600 species of flatfish, many of which are caught and eaten by humans. Carnivorous Plants Employ Bodyguard Ants. Carnivorous plants can have valuable allies in ants, benefiting from their poop and janitor, bodyguard and cutthroat services, researchers say. The carnivorous pitcher plant Nepenthes bicalcarata dwells in the nutrient-poor peat swamp forests of Borneo. It is not a very effective carnivore by itself — its pitcher-shaped leaves lack the slippery walls and viscous, elastic and strongly corrosive fluid that make those of its relatives such effective deathtraps. [Related: Hairy, crazy ants invade from Texas to Miss.] However, N. bicalcarata does apparently have unusual support on its side — the ant Camponotus schmitzi. The carnivorous plant has swollen tendrils at the base of each pitcher that serve as homes for the insects, and a food source in the form of nectar secreted on the pitcher rims. In return, the ants apparently provide a host of services for the pitcher plants.

View gallery Ants of the species Camponotus schmitzi, dragging especially large prey out of a pitcher. Sheena Iyengar: The art of choosing. Hans Rosling: No more boring data: TEDTalks. DNA, Ancestry and Human Migration. Quick Links to this Page What is genetic anthropology? Genetic anthropology is an emerging discipline that combines DNA and physical evidence to reveal the history of ancient human migration.

It seeks to answer the questions, "Where did we come from, and how did we get here? " DNA studies indicate that all modern humans share a common female ancestor who lived in Africa about 140,000 years ago, and all men share a common male ancestor who lived in Africa about 60,000 years ago. These were not the only humans who lived in these eras, and the human genome still contains many genetic traits of their contemporaries. Humanity's most recent common ancestors are identifiable because their lineages have survived by chance in the special pieces of DNA that are passed down the gender lines nearly unaltered from one generation to the next. How do genes tell the story of our ancient ancestors' migrations? Are Neanderthals part of modern human ancestry? Can mtDNA pass from father to child? The U.S. HapMap. Mysterious Chinese Fossils May Be New Human Species. Mysterious fossils of what may be a previously unknown type of human have been uncovered in caves in China, ones that possess a highly unusual mix of bygone and modern human features, scientists reveal.

Surprisingly, the fossils are only between 11,500 and 14,500 years old. That means they would have shared the landscape with modern humans when China's earliest farmers were first appearing. "These new fossils might be of a previously unknown species, one that survived until the very end of the ice age around 11,000 years ago," said researcher Darren Curnoe, a palaeoanthropologist at the University of New South Wales in Australia. "Alternatively, they might represent a very early and previously unknown migration of modern humans out of Africa, a population who may not have contributed genetically to living people," Curnoe added. The skeletons "They clearly had a taste for venison, with evidence they cooked these large deer in the cave," Curnoe said. Jutting jaws and flaring cheeks. Massive Extinction Fueled Rise of Crocodiles. A massive extinction between the Triassic and Jurassic eras paved the way for the rise of the crocodiles, new research suggests.

The researchers, who detail their work today (March 26) in the journal Biology Letters, found that although nearly all the crocodilelike archosaurs, known as pseudosuchia, died off about 201 million years ago, the one lineage that survived soon diversified to occupy land and sea. The lineage included the ancestors of all modern crocodiles and alligators. "Even though almost all the lineages except for one was extinct, the remaining survivors still did well in terms of morphology and body plans and the whole morphological diversity," said study co-author Olja Toljagic, an evolutionary biology researcher who was at the Ludwig Maximilian University of Munich at the time of the study. Dinosaur counterparts But around 201 million years ago, volcanic activity or a meteor killed off half the known species on Earth. Crocodile line Ecological opportunity. "Zombie" Fly Parasite Killing Honeybees. Fly_parasite_honeybee A parasitic fly landing on a honeybee.

Courtesy of Christopher Quock A heap of dead bees was supposed to become food for a newly captured praying mantis. Instead, the pile ended up revealing a previously unrecognized suspect in colony collapse disorder a mysterious condition that for several years has been causing declines in U.S. honeybee populations, which are needed to pollinate many important crops. This new potential culprit is a bizarre and potentially devastating parasitic fly that has been taking over the bodies of honeybees (Apis mellifera) in Northern California. John Hafernik, a biology professor at San Francisco State University, had collected some belly-up bees from the ground underneath lights around the University’s biology building. The team performed a genetic analysis of the fly and found that it is the same species that has previously been documented to parasitize bumblebee as well as paper wasp populations. Bee_parasite_fly_larvae.

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